The excellent folks at 84000 have completed translations of 22 (out of 49) of the Sutras in the Ratnakuta. Here is the master page with a link to each of the completed translations, and a placeholder for the ones they are still working on:
https://read.84000.co/section/O1JC114941JC14667.html

And here is a link to their overview page on the Tibetan version of the Ratnakuta:
https://read.84000.co/knowledgebase/heap-jewels.html

And below are some of the ones on my reading list:

https://read.84000.co/translation/toh69.html#introduction
Inspiring Determination [46 pages] is directed at reforming the conduct of sixty bodhisattvas who have lost their sense of purpose and confidence in their ability to practice the Dharma. The bodhisattva Maitreya leads them to seek counsel from the Buddha, who explains the causes these bodhisattvas created in former lives that resulted in their current circumstance. They make a commitment to change their ways, which pleases the Buddha, and this leads him to engage in a dialog with the bodhisattva Maitreya on how bodhisattvas, including those in the future age of final degeneration, the final half-millennium, should avoid faults and uphold conduct that accords with the Dharma.

https://read.84000.co/translation/toh65.html#summary
The Prophecy for Bhadra the Illusionist [38 pages]
While the Buddha Śākyamuni is residing at Vulture Peak Mountain, in the nearby city of Rājagṛha the accomplished illusionist Bhadra hatches a scheme to humiliate the Buddha and disprove his omniscience in order to win over the people of Magadha. The failure of Bhadra’s plan, in which he conjures the illusion of a resplendent courtyard that, to his dismay, cannot be undone, culminates in a series of surreal and magnificent visions that convince Bhadra of the superiority of the Buddha’s powers. This sūtra presents a colorful and often humorous narrative and contains teachings on illusion, emptiness, and the distinction between the illusionist’s mundane abilities and the Buddha’s miraculous display. The Buddha also teaches Bhadra forty-three sets of four qualities that together constitute the bodhisattva path.

https://read.84000.co/translation/toh61.html#summary
The Questions of Pūrṇa [118 pages]
In Veṇuvana, outside Rājagṛha, Pūrṇa Maitrāyaṇīputra asks the Buddha about the conduct of bodhisattvas practicing on the path to awakening. The Buddha replies by describing the attitudes that bodhisattvas must possess as well as their benefits. Then, at the request of Maudgalyāyana, the Buddha recounts several of his past lives in which he himself practiced bodhisattva conduct. At the end of the teaching, the Buddha instructs the assembly about how to deal with specific objections to his teachings that outsiders might raise after he himself has passed into nirvāṇa.

https://read.84000.co/translation/toh78.html#summary
In The Questions of Guṇaratnasaṅkusumita [11 pages], the sūtra’s interlocutor, Guṇaratnasaṅkusumita, asks the Buddha Śākyamuni whether there might be other buddhas in other realms whose names carry the power to produce awakening. The Buddha responds that there are, in fact, buddhas whose names are so efficacious that simply by remembering them, the disciple will be awakened. The Buddha then names the buddhas of the ten directions, their worlds and eons, and the specific effects that knowing each of their names will have on disciples with faith.

https://read.84000.co/translation/toh75.html#summary
In The Questions of Gaṅgottarā [8 pages], a laywoman named Gaṅgottarā leaves her home in the city of Śrāvastī and visits the Buddha Śākyamuni in Prince Jeta’s Grove, Anāthapiṇḍada’s Park. The Buddha asks her from where she has come, sparking a dialogue on the true nature of things. Among other things, they discuss the fact that, from the perspective of ultimate truth, all things, including Gaṅgottarā herself, are like magical creations, and thus no one comes or goes or pursues nirvāṇa. After their dialogue, the Buddha smiles. When Ānanda asks him why, he explains that a thousand tathāgatas of the past have already taught this discourse at this same location to a thousand different laywomen, all named Gaṅgottarā; and that through it they have all achieved nirvāṇa. The sūtra concludes with a b
rief explanation of the reasons why the present laywoman named Gaṅgottarā received this teaching and how it should be remembered in the future.

https://read.84000.co/translation/toh52.html#summary
The Teaching on the Indivisible Nature of the Realm of Phenomena [47 pages]
While the Buddha is in the Jeta Grove, he asks Mañjuśrī to teach on the nature of reality. Mañjuśrī’s account upsets some of the monks present in the gathering, who subsequently leave. Nevertheless, by means of an emanation, Mañjuśrī skillfully teaches the distraught monks, who return to the Jeta Grove to express their gratitude. The monks explain that their obstacle has been a conceited sense of attainment, of which they are now free. At the request of the god Ratnavara, Mañjuśrī then teaches on nonduality and the nature of the bodhisattva. Next, the Buddha prophesies the future awakening of Ratnavara and other bodhisattvas present in the gathering. However, the prophecies cause Pāpīyān, king of the māras, to appear with his army. In a dramatic course of events, Mañjuśrī uses his transformative power on both Pāpīyān and the Buddha’s pious attendant, Śāradvatīputra, forcing both of them to appear in the form of the Buddha himself. He then makes Pāpīyān and Śāradvatīputra teach the profound Dharma with the perfect mastery of buddhahood. Numerous bodhisattvas appear from the four directions, pledging to practice and uphold the sūtra’s teaching. The Buddha grants his blessing for the continuous transmission of the sūtra among bodhisattvas in the future.

https://read.84000.co/translation/toh83.html#summary
In The Questions of Bhadrapāla the Merchant [48 pages], the Buddha’s principal interlocutor is a wealthy merchant who asks him to explain what consciousness is, and what happens to it when one dies and is reborn. In his characterization of consciousness, the Buddha relies heavily on the use of analogies drawn from nature. The sūtra also reflects common cultural beliefs of ancient India, such as spirit possession. In addition, it presents graphic and vividly contrasting descriptions of rebirth in the realms of the gods for those who have lived meritorious lives and in the realms of hell for those who lack merit.